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# Installation

Apache DataFusion Java is published to
[Maven Central](https://central.sonatype.com/artifact/org.apache.datafusion/datafusion-java).
The JAR bundles the native library for Linux (x86_64, aarch64) and macOS
(x86_64, aarch64), so no separate native install is required on those
platforms. Windows is not yet supported by the published JAR; Windows
users need to build from source.

## Requirements

- **JDK 17 or newer.**
- Arrow needs access to `java.nio` internals. Add this to the JVM
  arguments of whatever runs your code:

  ```
  --add-opens=java.base/java.nio=ALL-UNNAMED
  ```

## Maven

```xml
<dependency>
    <groupId>org.apache.datafusion</groupId>
    <artifactId>datafusion-java</artifactId>
    <version>0.1.0</version>
</dependency>
```

## Gradle

```kotlin
dependencies {
    implementation("org.apache.datafusion:datafusion-java:0.1.0")
}
```

Arrow (`arrow-vector`, `arrow-c-data`, `arrow-memory-netty`) is pulled in
transitively — you do not need to declare it yourself.

## Build from source

If you are on Windows, on another platform without a bundled native
library, or want to run against unreleased changes, build from source:

```sh
git clone https://github.com/apache/datafusion-java.git
cd datafusion-java
make test
```

`make test` compiles the native Rust crate, then runs the JUnit tests
against it. The native library must be built before the JVM tests can
run.

Building from source requires a stable Rust toolchain (install via
[rustup](https://rustup.rs/)) in addition to the JDK.

The first build in a fresh checkout reaches out to
`raw.githubusercontent.com` to fetch the DataFusion `.proto` files used to
generate the `datafusion-proto` Java classes. Subsequent builds are
offline; the `download-maven-plugin` cache under
`~/.m2/repository/.cache/` satisfies them.

For development workflow details — running individual tests, the TPC-H
integration test data, code style, and how to update the underlying
DataFusion version — see the [Contributor Guide](../contributor-guide/development.md).